In DE 44 11 214 C2 it is disclosed how the sliding bearing bushing is inserted into the receptacle of the first fitting part. To this end, in a first step the first fitting part is fastened in a holder of a tool and the sliding bearing bushing is positioned on a mandrel of the tool. In a second step, the sliding bearing bushing is pressed into the receptacle of the first fitting part by a relative movement of the mandrel and the holder. The external dimension of the sliding bearing bushing is selected in the context of an interference fit to be slightly larger than the internal dimension of the receptacle of the first fitting part, so that material which collects on the trailing end of the sliding bearing bushing—relative to the movement of the mandrel—is displaced and serves as axial securing.